电子显微镜下的叶子
2010-08-25 21:39阅读:
电子显微镜下的叶子
图片和文字说明来源于
http://www.sciencephoto.com/。中文标题为本人翻译而来,原文中没有拉丁学名的无法确定到种。
银斑白里香(
Thymus vulgaris
Linn.)叶子的表面:Thyme leaf surface. Coloured Scanning Electron
Micrograph (SEM) of the underside of a leaf of the herb thyme,
Thymus vulgaris. Two types of leaf hairs (trichomes) are seen, and
stomata. Stomata appear as small, green circular structures; they
serve as pores for the exchange of gases from the leaf surface.
Unbranched multicellular hairs (blue) are seen which may have a
protective function or reduce evaporation from the leaf. Glandular
spherical struct
ures (yellow) are modified hairs; these are the source of the
aromatic oil of thyme. Thyme is used as a herb in cooking. It also
has medicinal properties. Magnification: x150 at 6x6cm size.
荷花叶子表面:Lotus leaf surface.
Coloured scanning electron micrograph (SEM) showing the
microstructures on the surface of a leaf from a lotus (Nelumbo sp.)
plant. These structures on the top of the leaf, along with a
waxy coating (removed here), help to repel water droplets better
than any other material in nature. This helps the leaves to stay
clean and stops fungi and other organisms from settling on them.
This 'lotus effect' is being studied so that similar mechanisms can
be implemented to produce 'self-cleaning' house paints. Here
stomatal pores (dark, oval) can also be seen. Magnification: x1830
when printed 10 centimetres wide.
樟树(
Cinnamomum
camphora (Linn.) Presl)叶子表面:Camphor leaf surface. Coloured
scanning electron micrograph (SEM) of the surface of a leaf of the
camphor tree (Cinnamomum camphora). Mid-green epidermal cells
provide support and secrete a waxy cuticle to protect the leaf and
limit water loss. Between the epidermal cells are paler green cells
containing stomata (leaf pores), through which gaseous exchange
occurs. Stomata are opened and closed by changes in pressure in the
guard cells on either side of the pore. Crystals of a substance
called camphor can be extracted from the leaves and wood of C.
camphora. It is used in herbal medicine to treat many complaints.
Magnification: x330 when printed 10cm wide
长角豆(
Ceratonia
siliqua Linn.)叶子表面:Carob tree (Ceratonia siliqua) leaf
surface, coloured scanning electron micrograph (SEM). The
blue/green structures are stomata (leaf pores), the site of gaseous
exchange in a plant. The opening and closing of the stomata is
controlled by the semi-circular guard cells, which swell and become
turgid to close the openings. Magnification: x360 when printed at
10 centimetres wide.
木槿叶子的表面:Hibiscus leaf
surface, coloured scanning electron micrograph (SEM). The yellow
structures are oil glands. The spikes act as a deterrent to
predators. Magnification: x90 when printed at 10 centimetres
wide.
马铃薯(
Solanum
tuberosum Linn.)叶子的表面:Potato leaf (Solanum tuberosum) surface,
coloured scanning electron micrograph (SEM). It is covered in
hair-like growths called trichomes. The long spiky trichomes
protect the plant against predators and water loss through
evaporation. The rounded trichomes secrete oils that are irritating
to predatory insects. Magnification: x75 when printed at 10
centimetres wide.
迷迭香(
Rosmarinus officinalis
Linn.)的叶子:Rosemary leaf. Coloured scanning electron micrograph
(SEM) of the surface of a young rosemary (Rosmarinus officinalis)
leaf. The leaf surface comprises epidermal cells (green). On the
leaf surface are two types of trichome (hair process). Globular oil
glands (yellow) secrete oil. Hair cells (grey), which may be
branched or unbranched, may protect the leaf against water loss, or
against insects. Rosemary is used widely in cookery and herbal
medicine. It is used to treat depression, migraine, rheumatism,
arthritis, neuralgia and muscle injuries. Magnification: x400 when
printed 10 centimetres wide.
薰衣草(
Lavandula
angustifolia Mill)的叶子:Lavender leaf. Coloured scanning
electron micro- graph (SEM) of a section through the leaf of a
lavender plant (Lavandula augustifolia). Numerous dense branched
hairs (trichomes) cover the leaf's surface. These have both a
protective function against pests and serve to reduce evaporation
from the leaf. The rounded structure (pale brown, lower centre) is
an oil gland, which produces the plant's aromatic oil. Below this
is the sectioned leaf, with the impermeable cuticle uppermost,
supported by epidermal cells. Lavender is a herb which grows wild
in the Mediterranean region, but is farmed all over the world.
Magnification: x380 at 6x7cm size. x590 at 4x5'
木犀榄(
Olea
europaea Linn.)叶表面的毛:Leaf hairs. Coloured scanning electron
micrograph (SEM) of the scale-like leaf hairs (trichomes) on an
olive tree leaf (Olea europaea). These leaf hairs prevent
evaporative water loss during dry conditions or high winds. They
help the olive tree to survive in the hot and seasonally dry
climates in which it lives. Gas content in the leaf is regulated by
its stomata (one at lower right). These are pores which are opened
and closed by their surrounding guard cells (brown). Magnification:
x222 at 6x7cm size. x350 at 4x5'
烟草(
Nicotiana
tabacum Linn.)叶表面的毛:Tobacco leaf hairs. Coloured scanning
electron micrograph (SEM) of leaf hairs (brown) on the surface of a
tobacco leaf Nicotiana tabacum. These large glandular trichomes
secrete distasteful chemicals to deter pests from feeding on the
leaves. Magnification: x160 at 6x6cm size. x260 at 4x5 inch
size.
芦荟叶的气孔:Aloe stoma. Coloured
scanning electron micrograph (SEM) of a stoma (centre) on the
surface of a leaf from an aloe (Aloe sp.), a type of succulent
cactus. A stoma is an opening in a leaf's surface which helps
regulate gas exchange between the leaf interior and the atmosphere.
It is opened or closed by its two bordering guard cells (green,
below blue layer). Magnification: x325 at 6x7cm size. x520 at
4x5'
欧洲红豆杉(Taxus
baccata)叶表面的气孔:Yew stomata. Coloured scanning electron micrograph
(SEM) of stomata (holes) on the surface of the leaf of an English
yew (Taxus baccata). Stomata are holes which regulate gas and water
exchange between the leaf and the atmosphere. During the day they
open to allow the exchange of gases during photosynthesis, closing
at night to prevent water loss. They are opened and closed by two
bordering guard cells (not seen) below this top layer. This yew is
a long-lived poisonous tree which inhabits cool, hilly areas
throughout Europe and northern Asia. Magnification: x375 at 6x7cm
size. x580 at 4x5 inch size.
百岁兰(
Welwitschia
mirabilis Hook.f.)的叶子:Welwitschia plant leaf. Coloured
scanning electron micrograph (SEM) of a section through a leaf of
the desert plant Welwitschia mirabilis. Large vascular bundles
(orange/grey) are seen running through the leaf. These carry water
and nutrients to and from the leaf. This plant lives in the arid
desert of south-western Africa. It extracts all the moisture it
needs from fogs which cover the desert at times. It only has two
leaves, which grow from a thick root embedded in the ground. The
leaves grow throughout the life of the plant, which may be as long
as 2000 years. Magnification: x30 at 6x7cm size. x50 at 4x5'
圣诞蔷薇(暗叶铁筷子、嚏根草)(
Helleborus niger
Linn.)的叶子:Christmas rose leaf. Coloured scanning electron
micrograph (SEM) of a section through the leaf of the Christmas
rose (Helleborus niger). The upper surface of the leaf is at top.
Numerous vertical cells containing chloroplasts (small spheres) are
seen beneath the surface. These are the site of photosynthesis, the
process by which plants use sunlight to turn carbon dioxide into
sugars. At upper left and right are vascular bundles (blue), part
of the network of veins which transports water and nutrients to and
from the leaf. Stomata (pores regulating gaseous exchange) are seen
on the lower surface of the leaf in lower frame. Magnification:
x120 at 6x7cm size. x190 at 4x5'